Thanks Negarcia for your reply.
Yes, the kids know we have separated. Sometimes WH will call in as he is in the area (quite often it is when most of the kids are at school) or alternatively because he misses the kids or is taking them to an activity like swimming lessons. The kids aged 3 to 9 years had differing responses to his leaving which was largely age dependant but generally speaking they were upset and blindsided as it all came out of the blue for them as our marriage is very amicable and there wasn't really any tension they saw.
I have tried to make him understand this is my place now and he has made his choice but it doesn't seem to be hitting home but then his history says he has boundary issues. It's hard because I do like chatting with him so don't really mind him around although I can't reconcile myself to his choices and decision making processes and I know I should put my foot down more but I'd like to keep things amiable as it is easier to work things out together than if we are fighting with each other.
I agree that getting along is better than fighting and I also liked talking to my husband but the day I decided to put my foot down and stopped answering his calls and he only talked to the kids it killed him inside. He told me he would rather me yell at him then give him the silent treatment.
I know you are trying to be civil but some advice I got on here from Kal was that you are allowing him to feel like he has the upper hand in a way by letting him still live the norm by talking to you the way you used to and to not have those boundries. It was hard for me but I set those boundries for myself not for him and it gave me such peace of mind knowing that I could do it on my own and also be strong for the kids and I. Remember that this is something he decides to do to your family, why allow him to have sooo much control? I know the kids have a big part in it and it's great he's involved with them but you need to set those boundries that he needs to learn to follow for your own good.